Multiple crayon for drawing simultaneously a plurality of spaced parallel lines



June 8, 1954 C CRONBERGER 2,680,296

MULTIPLE CRAYON FOR DRAWING SIMULTANEOUSLY A PLURALITY 0F SPACED PARALLEL LINES Filed Dec. 5, 1952 2 Sheets-Sheet 1 Patented June 8, 1954 UNITED STATES PATENT OFFICE MULTIPLE CRAYON FOR DRAWING SIMUL- TANEOUSLY A PLURALITY F SPACED PARALLEL LINES Claims.

This invention relates to multiple crayons for drawing simultaneously a plurality of spaced parallel lines. Such crayons are being used by musicians to form the lines of the staff in music, or by draftsmen to line their drawings preparatory to add specifications, legends or similar written information to them, by engineers who wish to make their own cross-section papers, etc.

One object of this invention is to improve prior art the stiluses or drawing tools of this kind.

Another object of this invention is to provide a simple and rugged multiple crayon for drawing simultaneously a plurality of parallel lines which crayon can be manufactured at less cost than any prior art drawing tool or stilus of this kind.

Another object of this invention is to provide a drawing tool for drawing simultaneously a plurality of parallel lines of uniform size and a desired distance spaced apart which tool has resilient means for exerting a transverse clamping pressure upon the leads forming a part of the tool and also has resilient means constituting a common abutment for the ends of the leads remote from the drawing ends thereof.

Further objects, advantages and features of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to 1 and forming part of this specification.

For a better understanding of the invention reference may be had to the accompanying drawing in which Fig. 1 is a front view of a multiple stilus embodying the invention;

Fig. 2 is a side elevation of the structure shown in Fig. 1;

Fig. 3 is a front elevation of the same structure as shown in Fig. 1 with the constituent parts thereof in another position;

Fig. 4 is a top plan view of another embodiment of the invention with portions of the housing of the stilus broken away to better show the parts which are arranged inside of the housing;

Fig. 5 is substantially a section along 5-5 of Fig. 4;

Fig. 6 is an elevation of the head of a multiple pencil embodying the invention;

Figs. 7 to 9 are families of spaced lines produced by a multiplepencil having a pencil head of the kind shown in Fig. 6;

Figs. 10 and 11 are isometric illustrations of another head of a multiple encil embodying the invention; and

Fig. 12 is a rail guide which enables to vary and control the spacing between the parallel lines produced by means of a multiple pencil of the kind shown in Figs 4 and 5.

Referring now to Figs. 1 to 3, inclusive, reference numeral I has been applied to a handle member which is substantially U-shaped and is provided with a plurality of transverse grooves at one of the lateral faces thereof. Handle member I has a plurality of bores lb, e. g. six bores, of which each is intended to receive and receives one of six leads 2. project beyond handle member I. spaced straight parallel lines or parallel curves may be drawn on a sheet of paper, or equivalent drawing material, by moving the handle member over the drawing material with the lower ends of leads engaging the drawing material under slight pressure. Families of parallel lines which may be produced in this fashion are shown in Figs. '7 to 9, inclusive. The upper ends of leads 2 are in engagement with a lead-supporting block. Lead supporting block comprises a first layer 30 consisting of a material in the nature of porous rubber having a relatively high density and a second layer 3b consisting of a material in the nature of porous rubber having a smaller density than the material of which the first layer 3a consists. Both layers 3a and 31) may be made of natural rubber, or of an elastomer, i. e. of a synthetic material having physical properties" similar to those of natural rubber. Membrane 4 which may consist of such materials as rubber or chamois is sandwiched between layers 3a and 3b and the ends of leads 2 remote from the writing ends thereof rest and abut against membrane 4. Layer 3a is provided with a plurality of lead receiving bores 30 of which each accommodates one of the leads 2. The lateral boundary surface of each of bores 30 is in frictional engagement with the entire periphery, or perimeter, of one of the leads 2. A rubber band 5 is wound around both layers 3a and 3b and has a plurality of spaced bores 5a. The lateral wall of each of these bores is in frictional engagement with one of the leads 2. The ackage consisting of the parts 3a, 3b, 4 and 5 is arranged between the shanks of a substantially U-shaped clamping member 6 which consists of a highly resilient material such as, for instance, steel. Both shanks of clamping member 5 have an inherent spring bias tending to reduce the spacing between the lower edges 6a thereof. The lower edges 6a of clamping member 6 are turned in upward direction and form tubular elements or sleeves 6b receiving pins la which form an integral part of a pair of handles 1' of bent wire. Sleeves 6b are adapted to be inserted into the transverse grooves la formed in handle member I thus fixing the position of clamping member 6 relative to handle member .1.

The lower ends of leads 2 A family of Handles 7 rest against the shanks of clamping member 6. When handles 7 are pressed in the direction of the arrows A of Fig. 2 against the spring bias of clamping member 5, this causes an increase of the distance between the sleeves 61). Consequently clamping member 6 may be moved either in upward or in downward direction, as desired. Engagement of sleeves 6b with another transverse groove la in handle member i than the one in which sleeves 6b originally rested may be effected by taking the pressure ofi handles 1. Since the package consisting of parts 311, 3b, 4 and 5 is arranged between the shanks of clamping member 6, shifting of the latter in downward or upward direction causes the lower or writing ends of leads 2 to project more or less from the lower face If of the handle member I, which may be referred to as the writing head of the pencil.

The purpose of the lower resilient layer 3a which may consist of dense sponge rubber is to exert a substantial transverse or radial pressure upon the leads 2 to hold the leads 2 in frictional engagement in the composite structure 311, 3b, 4 and 5. Since the above transverse or radial pressure is substantially equal along the entire periphery or perimeter of each lead 2, the leads 2 will have little tendency to be tilted laterally, but will rather tend to extend in substantially parallel direction from the composite structure 3a, 3b, 4 and 5. The purpose of the upper resilient layer 3b is to equalize dilferences in length and differences in axial pressure exerted upon the leads 2 by the writing surface along which they are moved. The friction between the writing surface and the leads 2 may vary from lead to lead mainly depending upon the geometrical configuration of the writing end or tip of each lead. The membrane 4 and the resilient rubber layer 31) compensate for differences with regard to the friction of the various leads 2 as well as for differences in the length thereof which may amount to as much as or even slightly more.

It is possible to substitute for the two resilient layers 3a, 3b a single resilient layer capable of performing the functions of the two layers, but the structure comprising two separate resilient layers is preferable because the problem involved is of a dual nature calling for two different means for an ideal solution thereof, i. e. for two resilient substances having different physical properties or different degrees of resiliency.

The structure shown in Figs. 4 and 5 comprises a handle member I substantially in the shape of a square box. This box comprises two longitudinal metal strips ma, two transverse metal strips lilb, a cover plate 400 and a bottom plate Hid. All these parts may be made of aluminum. Transverse metal strip illb is provided with a plurality of spaced parallel bores I] each receiving one of a pluralty of leads 2. A carriage including a pair of spaced bars l2a, [2b is arranged within the box-shaped handle member i. Bar 152a is provided with a plurality of bores or holes each receiving one of the plurality of leads 2. The composite structure 3a, 3b, i and 5 which is arranged between bars 12a, [21) is the same as that shown in Figs. 1 to 3 and designated by the same reference signs. 3a is a layer of relatively dense sponge rubber, 3b is a layer of relatively porous sponge rubber, 4 is a resilient membrane separating layers 3a and 3b and 5 is a multiperforated rubber ribbon for packaging parts 3a, 3b and d. The leads 2 pass through the perforations 5a which are provided in rubber ribbon 5 and the ends of leads 2 re- Iii) mote from the writing ends thereof restagainst the membrane 4. Screw-threaded stem I3 is firmly attached to the bar I21) and the end of stem #3 remote from bar (2b is passed through a bore [5a. in a fixed transverse member I5 arranged Within box-shaped handle member I. Topplate ltlc and bottom plate [0d are each provided with a slot l6 for the passage of the outer rim of a screw nut l4 riding on screwthreaded stem i3. Thus screw-nut 16 can readily be manipulated from the outside of the boxshaped handle member I. If screw-nut I4 is turned in one direction, leads 2 are moved into the handle member I, if screw-nut I4 is turned in the other direction, the leads 2 are moved to the outside of handle member 2. The various parts of handle member I may be assembled by means of screws I 7 or any other suitable fastenmg means.

Considerable difficulties may be encountered in making the cross-member, lead-head, or writinghead [6b of the multiple stiluses according to this invention in case that it is desired to narrowly space the leads 2 in order to be able to produce families of narrowly spaced parallel lines. Fig. 6 is the front elevation of a crossmember or lead-head which can readily be manufactured and which makes it possible to draw various families of spaced parallel lines having relatively narrow or relatively wide spacings, as desired. The cross-member or lead-head Iilb shown in Fig. 6 comprises three parallel lines of spaced lead-receiving bores or holes H. The holes H in the first line l8 are, for instance, spaced the holes in the second line [9 are spaced A" and the same spacing of A" prevails between the holes of the third line 26. The relative displacement of the three lines of holes i8, i9 and 20 makes for a large variety of families of parallel spaced lines of which three are shown in Figs. '7 to 9, inclusive. It is apparent that by filling the holes H of all three lines 18, 59 and 29 with leads families of parallel lines may be produced which are as little as apart, though the closest spacing of the holes in the cross-member or lead-head is not closer than V Where a multiplicity of lines l8, I9, 20 of holes H is provided in the cross-member or lead-head illb, the lead-receiving layer 3a of resilient material arranged behind the crossmember or lead-head Hlb is provided with a system of lead-receiving bores having the same geometrical configuration as the system of holes H in crossmember or lead-head [01).

Another difliculty that may be encountered in manufacturing cross-members or lead-heads for pencils of the type shown in Figs. 4 and 5 may be due to the fact that it is not easy to drill straight long thin and narrowly spaced holes. To avoid the aforementioned difiiculties the cross-member or lead-head of such pencils may be made up of two separate sections which may be readily produced by appropriate processes as, for instance, plastic molding. The sections or lead guiding members 2!, 2-2 of the lead-head shown in Figs. 10 and 11 each have a group of semi-cylindrical grooves 23. The grooves 23 of the lead guiding member 2! are arranged in registry with the identical grooves 23 in the lead guiding member 22. Thus the semi-cylindrical grooves 23 in both lead guiding members define jointly cylindrical lead-receiving bores or passageways equivalent to the bores or passageways indicated in Figs. 4 and 5 by the numeral H. Fig. 10 is an exploded view of the two lead guiding members 3) 2|, 22 and Fig. 11 shows these two members in assembled position.

Drawing tools of the kind shown in Figs. 1 to 3, inclusive, or shown in Figs. 4 and 5, may be moved either free hand along the surface of a sheet of paper, or a straight edge may be used for properly guiding the tools.

Referring now to Fig. 12, reference letter T indicates generally a portion of a T-square and reference letter D indicates generally a multiple drawing tool of the general character illustrated in Figs. 4 and 5. The part G is a guide rail having an axial slot 39. The straight edge 3! of guide rail G rests against the straight edge 32 of T-square I. Drawing tool D and guide rail G are hingedly connected at 33, thus enabling to vary at will the angle formed between guide rail G and the straight line 34 interconnecting the lead holes I! of drawing tool D. The spacing between the lines drawn by the leads in lead holes H is a function of angle 0. Hence the spacing between the lines drawn by tool D may be changed by changing the angle 0. Hinge 33 is adapted to be tightened in any desired position to fix the angle 0 for the duration of any specific job intended to be accomplished by means oi drawing tool D.

While provision of a guide rail G is the preferred means for varying the spacing between lines within the limits given by the sine func- 3 1 tion, other means than the guide rail may be used for the same end, e. g. the housing of the drawing tool D may be provided with a number of guide surfaces arranged at different angles and adapted to cooperatively engage a straight edge of a T-square, a triangle, or the like, to guide tool D along that straight edge while maintaining constant the angle formed between the housing of the drawing tool and the straight edge.

Having disclosed several preferred embodiments of the invention, it is desired that the same be not limited to the particular structures disclosed. It will be obvious to any person skilled in the art that many modifications and changes may be made without departing from the broad spirit and the scope of the invention. Therefore it is desired that the invention be interpreted as broadly as possible and that it be limited only as required by the state of the prior art.

I claim as my invention:

1. A multiple crayon for drawing simultaneously a plurality of spaced parallel lines comprising a plurality of leads, a block of a resilient material for supporting said plurality of leads, said block comprising a first layer of a material in the nature of porous rubber having a relatively high density and a second layer of a material in the nature of porous rubber having a smaller density than the material of which said first layer is made, said first layer having a plurality of parallel spaced bores each accommodating one of said plurality of leads, each of said plurality of bores exerting with the lateral boundary surface thereof transverse pressure upon said one of said plurality of leads accommodated therein, and said second layer providing a joint resilient abutment for the ends of said plurality of leads remote from the writing ends thereof, said first layer and said second layer being separated by a third layer in the nature of a membrane, the ends of said plurality of leads remote from the writing ends thereof physically engaging said membrane layer.

2. A multiple crayon for drawing simultaneously a plurality of spaced parallel lines comprising a plurality of leads, a block of a resilient material for supporting said plurality of leads. said block including a first layer of a material in the nature of porous rubber having a relatively high density and a second layer of a material in the nature of porous rubber having a smaller density than the material of which said first layer is made, said first layer having a plurality of parallel spaced bores each accommodating and frictionally engaging one of said plurality of leads, said second layer being arranged adjacent the ends of said plurality of leads remote from the writing ends thereof, a layer in the nature of a membrane sandwiched between said first layer and said second layer in abutting relation with said plurality of leads, and a rubber band wound around said first layer and said second layer, said rubber band having a plurality of spaced bores for the passage of said plurality of leads.

3. A multiple crayon as specified in claim 2 wherein said block is supported by a handle member, said handle member having means for adjusting said block in a direction longitudinally of said plurality of leads to jointly adjust said plurality of leads relative to said handle member.

4. A multiple crayon for drawing simultaneously a plurality of spaced parallel lines comprising a plurality of leads, a handle member having a plurality of parallel spaced bores each loosely receiving one of said plurality of leads, and a lead-support movable relative to said handle member in a direction longitudinally of said plurality of leads, said lead-support including a first layer of a material in the nature of porous rubber having a relatively high density and a second layer of a material in the nature of porous rubber having a smaller density than the material of which said first layer is made, said first layer having a plurality of parallel spaced bores in registry with said plurality of parallel spaced bores in said handle member and each of said plurality of bores in said first layer frictionally engaging one of said plurality of leads, said second layer being arranged adjacent the ends of said plurality of leads remote from the writing ends thereof, a layer in the nature of a membrane separating said first layer from said second layer arranged in abutting relation with said plurality of leads, and a rubber band wound around said first layer and said second layer and having a plurality of spaced bores for the passage of said plurality of leads.

5. A multiple crayon for drawing simultaneously a plurality of spaced parallel lines comprising a plurality of leads, a handle member having a plurality of parallel spaced bores arranged out of registry along a plurality of spaced lines, some of said plurality of bores receiving one of said plurality of leads, and a lead-support movable relative to said handle member in a direction longitudinally of said plurality of leads.

References Cited in the file of this patent UNITED STATES PATENTS 

